package bigPack.dao.impl;

import bigPack.utils.JdbcUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.List;

public abstract class BaseDao {
    //使用DBUtils 操作数据库
    private QueryRunner queryRunner=new QueryRunner();
    public int update(String sql,Object ... args){
        Connection connection= JdbcUtils.getConnection();
        try {
            return queryRunner.update(connection,sql,args);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }finally {
            JdbcUtils.close(connection);
        }
        return -1;
    }

    /*
    * 查询返回一个javabean的sql语句
    * */
    public<T> T queryForOne(Class<T> type, String sql,Object ... args){
        Connection con=JdbcUtils.getConnection();
        try {
            return queryRunner.query(con,sql,new BeanHandler<T>(type),args);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }finally {
            JdbcUtils.close(con);
        }
        return null;
    }

//查询返回多个javabean的sql语句
    public <T> List<T> queryForList(Class<T> type, String sql,Object ... args){
        Connection con=JdbcUtils.getConnection();
        try {
           return queryRunner.query(con,sql,new BeanListHandler<T>(type),args);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }finally {
            JdbcUtils.close(con);
        }
        return null;
    }


//返回一行一列的sql语句
    public Object queryForSingleValue(String sql,Object ... args){
        Connection conn=JdbcUtils.getConnection();
        try {
            return queryRunner.query(conn,sql,new ScalarHandler(),args);
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            JdbcUtils.close(conn);
        }
        return null;
    }

}
